Method of preparing metal borings and the like particularly for use in furnaces



Patented Nov. 25, 192d,

THOMAS GILMORE, 311i, OF BROOKLYN, NEW YORK, ASSIGNOR TO THE GENERAL METAL BBIQUETTE CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

METHOD OF PREPARING METAL BORING-rs AND THE LIKE PARTICULARLY FOR USE IN FURNACES.

No Drawing.

To all whom it may concern.

Be it known that I, THoMAs GILMORE, Jr., a citizen of the United States of America, and a resident of the borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful Improvements in Methods of Preparing Metal Borings and the like Particularly for Use in Furnaces, of which the following is a specification.

My invention relates to the treatment of cast iron and steel borings, turnings or similar material, and particularly to the preparation of such material for use in the eupola furnace. Cast iron or steel in the condition of borings, turnings, and the like, consists almost entirely of metal, not more than about 3% of FeO being generally present in such material. When these borings or turnings are melted down in a loose condition, the results are unsatisfactory, on account of considerable loss by oxidation and the consequent formation of hard iron which is diflicult-to machine and therefore is only available for work of the cheapest character. For this reason the briquetting or compression of such borings or like material offers considerable advantages in that it facilitates the melting down of the material in cupola practice. According to my present invention cast iron borings or similar material and a solution of from 1 to 5% of acid sulphite liquor are mixed in any suitable way, for instance in a paddle mixer followed by an edge-mill, the iron or like material being in this manner thoroughly coated with the solution. The mixing action results in, or is accompanied by, a heating of the mixture which is thereupon passed as rapidly s possible through a press preferably a vertical. feed rotary press capable of exerting very high pressures. Such a press may be constructed for instance as disclosed in my application for United States Letters Patent, Serial .No. 542,826. The sulphite liquor as is well known contains gum which it has taken up from the pulp material and this gum acts as a binder to hold together the briquettes formed in the press. At the time of leaving the press the briquets are not yet set and not yet water-proof, but within a short time, generally not exceeding 15 minutes, they become fully set and strong Application filed November I, 1922. Serial No 598,997.

enough to prevent crumbling or breaking and may then be put into a cupola furnace or to any other metallurgical use desired. Before, during, and after the briquetting operation, the sulphuro-us acid contained in the sulphite liquor, presumably oxidized to sulphuric acid, attacks the iron to an extent depending upon the amount of sulphite liquor in the mixture and converts the iron into iron sequioxide Fe O which has cementing properties and acts to complete the setting of the briquette. This reaction is extremely rapid in the case of cast iron borings, the briquettes in that case being too hot to handle when they emerge from the press.

Instead of acid sulphite liquor I might use any equivalent acidified gum, that is I might use any agent having both acidic and gummy (agglutinant) characteristics, and I desire it to be understood that the appended claims are to be interpreted as covering such equivalent.

The briquettes coming from the press are simply exposed to the air and will become hardened and set within about 15 minutes as above described.

The procedure that I have described above with reference to the briquetting of: cast iron or steel borings, turnings, or the like, may also be used for briquetting zinc, brass or other metals in the condition of borings, turnings or in other comminuted form, it being understood that such material is tobe entirely or chiefly metallic, that is to say, oxides, if present at all should form only a small proportion of the material.

Various modifications may he made without departing from the nature of my invention as set forth in the appended claims.

I claim:

1. The herein described method which consists in mixing metal borings or similar material with an agent containing a gum and an acid which will react with the metal of the material, subjecting the mixture to high pressure during the chemical reaction be tween said agent and the material, and exposing the resulting compressed mass to the atmosphere.

2. The herein described method which consists in mixing metal borings or similar material with an agent containing a gum and anacid whieh will react With the metal of the: in rteriiil, zind subj eot-in g the ini'ktu'fe to pressure.

3. The herein described method which consi's'ts in mixing metal b'orings'or silnii'arm'at'erial with it small percentage of acid su'iphite liquor, subjecting the mixture rapidly tohigh pressure, and exposing the resulting compressed mass to the atmosphere to 0b- 1 tain hardening and set-ting.

4. The herein described method which i eohsis'ts in mixing cast iron or steel bo'rings or the like with from 1 to 5% of acid sulphite liquor, briquetting the mixture under high pressure, and exposing the briquettes to the air to obtain hardening and setting.

In testimony whereof I have hereunto set my hand.

THOMAS GILMORE, Jn. 

